Home / Milling / Mill Tooling / Boring Heads / Boring Head, R-8 3″ Square, 1″ Boring Bars Armstrong Boring Head, R-8 3″ Square, 1″ Boring Bars Armstrong$149.00 Category: Boring Heads Description Description Armstrong 3″ Boring Head w/ R8 Shank, 1″ Boring Bars w/ 1/2″ Reducer Related products Boring Head, Straight Shank 5/8″, 1-7/8″ Diameter $59.00 Read more Boring Head, R-8, Bridgeport, Diameter 2″, Item #L6101 $225.00 Read more Boring Head, CAT 40, 3″ Diameter, Criterion, Item # L62340 $249.00 Read more Boring Head, 1/2″ Straight Shank, Diameter 2 1/2″, Everede $75.00 Read more